17 - systemic protozoal infections

Question 1

(toxoplasmosis)

1. cause?
2. definitive host?

Answer 1

1. toxoplasma gondii
2. cats

(dogs and other mammals serve as intermediate hosts)

Question 2

(toxoplasmosis)

1. routes of infection?

Answer 2

1. raw meat

food, water, soil contaminated with cat feces containing oocysts

3. transplacental

Question 3

(toxoplasmosis)

(stages of infection)

1. intestinal replication and oocyst sheeding occur in cats only
2. what is this stage called?
3. how long is sheeding stage?

Answer 3

2. the sporozoite stage
3. 2 weeks

Question 4

(toxoplasmosis)

(stages of infection)

Question 5

(toxoplasmosis)

(cx)

1. more frequent in cats, similar in dogs
2. depend on organs effeced
3. name ALL of the clincal signs!

Answer 5

Question 6

(toxoplasmosis)

(dx)

1. what is the best way to dx an active infection?
2. can sometimes see intracellular inclusions on impression smears or biopsy
3. fecal oocysts rarely identified because shedding occurs before Cx

Answer 6

1. serum IgM titer (elevates a few weeks after exposure and coincides with Cx)

(serum IgG stays elevated for life - doesn’t distinguish prvious from active infection)

Question 7

(toxoplasmosis)

1. tx of choice?

Answer 7

1. clindamycin

Question 8

(toxoplasmosis)

Question 9

(neospirosis)

1. cause?

Answer 9

1. neospora caninum (a coccidia)

Question 10

(neospirosis)

1. definitive hosts?

Answer 10

1. dogs and wild canids

(other animals like cattle and deer are intermediate hosts)

Question 11

(neospirosis)

1. infection occurs how?

Answer 11

1. via ingestion of infected meat, or transplacentally

Question 12

(neospirosis)

1. dogs shed oocysts in their feces, which can infect cattle and cause what?

Answer 12

1. abortion

Question 13

(neospirosis)

(cx)

1. what signs are the most common?

Answer 13

1. neuromuscular signs

Question 14

(neospirosis)

1. dx based on what?

Answer 14

1. Cx and positive titer for Neospora

Question 15

(neospirosis)

1. tx?

Answer 15

1. similar to toxoplasmosis

clindamycin, TMS, pyrethamine

Question 16

(hepatozoonosis)

1. tick borne disease caused by what two things?

Answer 16

1. hepatozoon americanum or hapatozoon canis

Question 17

(hepatozoonosis)

1. H. americanum typically found where
2. transmitted by what tick?

Answer 17

1. gulf coast region
2. gulf coast tick, amblyomma maculatum

Question 18

(hepatozoonosis)

1. infection occurs when dog does what?

Answer 18

1. dog ingests infected tick

Question 19

(hepatozoonosis)

(path)

1. after ingestion, H. americanum disseminates and forms tissue cysts, esp where?

Answer 19

1. muscle tissues

Question 20

(hepatozoonosis)

(Cx)

Question 21

(hepatozoonosis)

Question 22

(hepatozoonosis)

1. how is h. americanum dx?

Answer 22

1. id of organisms in skeletal musc biopsies

Question 23

(hepatozoonosis)

1. for H. americanum, tx doesn’t eliminate H. americanum from tissues
2. what abx are used?

Answer 23

2. clindamycin, TMS, pyrimethamine

Question 24

(Leishmaniasis)

Question 25

(Leishmaniasis)

Question 26

(Leishmaniasis)

Question 27

(Leishmaniasis)